Energy storage device, and server and method for controlling the same

ABSTRACT

Energy storage devices, servers, and methods for controlling the same are disclosed. The energy storage device can include at least one battery pack, a network interface configured to exchange data with a server, and a connector that receives alternating current (AC) power from an internal power network or outputs AC power to the internal power network. Energy storage device can also include a power converter configured to convert the AC power from the internal power network into direct current (DC) power based on the information about the power to store when information about power to store is received from the server, or, convert DC power stored in the battery pack into AC power based on the information about the power to output when information about power to output to the internal power network is received from the server. Accordingly, energy may be more efficiently stored.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Korean Patent Application No.10-2012-0068058, filed on Jun. 25, 2012 in the Korean IntellectualProperty Office, which is hereby incorporated by reference as if fullyset forth herein.

BACKGROUND

1. Field

The present disclosure relates to energy storage devices, servers, andmethods. More specifically, the present disclosure relates to energystorage devices, servers, and methods which are capable of efficientlystoring and controlling energy.

2. Discussion of the Related Art

Fossil fuels, or non-renewable energy resources, such as petroleum andcoal are depleting at an increasing rate. As a result, interest inalternative or renewable energy sources, including sunlight (i.e., solarpower), wind, hydraulic, etc. is on the rise.

SUMMARY

Unfortunately, devices and systems for storing and methods ofcontrolling energy generated from alternative energy sources have manyshortcomings. For example, there is a lack of a device and controlsystem that reliably supplies or stores energy made from renewableenergy sources. Accordingly, an energy storage device which is capableof efficiently storing energy, a server, and a method for controllingthe same is disclosed. Although the disclosed devices, servers, andmethods are particularly well-suited for renewable energy sources, theymay also be applied to non-renewable energy resources.

In an illustrative embodiment, an energy storage device is provisioned.The energy storage device can include at least one battery pack, anetwork interface that exchanges data with a server, and a connectorthat receives alternating current (AC) power from an internal powernetwork or outputs AC power to the internal power network. In addition,energy storage device may include a power converter configured toconvert the AC power from the internal power network into direct current(DC) power based on the information about the power to store wheninformation about power to store is received from the server, or,convert DC power stored in the battery pack into AC power based on theinformation about the power to output when information about power tooutput to the internal power network is received from the server.

In some embodiments, a server is disclosed. Server can include a networkinterface that receives information about renewable power generated by arenewable energy generation device, information about commercial powersupplied to an internal power network and information about load powerconsumed in the internal power network. In addition, server may includea processor configured to calculate power to store in at least oneenergy storage device through the internal power network or from theenergy storage device to the internal power network based on at leastone of the load power information, the commercial power information andthe renewable power information. The network interface transmitsinformation about the calculated power to store or information about thecalculated power to output to the energy storage device.

In an embodiment, a method for controlling an energy storage device isdisclosed. The method can include converting alternating current (AC)power from an internal power network into direct current (DC) powerbased on information about power to store when the information about thepower to store is received from a server and storing the converted DCpower. In addition, the method may include converting the stored DCpower into AC power based on information about power to output to theinternal power network when the information about the power to output isreceived from the server, and outputting the converted AC power to theinternal power network.

A method for controlling a server is also disclosed. The method caninclude receiving information about renewable power generated by arenewable energy generation device and information about commercialpower supplied to an internal power network and receiving informationabout load power consumed in the internal power network. In addition,the method may include calculating power to store in an energy storagedevice through the internal power network or power to output from theenergy storage device to the internal power network based on at leastone of the load power information, the commercial power information, andthe renewable power information. The method may further comprisetransmitting information about the calculated power to store orinformation about the calculated power to output to the energy storagedevice.

Advantages and features of the disclosure in part may become apparent inthe description that follows and in part may become apparent to thosehaving ordinary skill in the art upon examination of the following ormay be learned from practice of the disclosure. The advantages andfeatures of embodiments of the present disclosure may be realized andattained by the structures and processes described in the writtendescription, the claims, and in the appended drawings.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory andshould not be construed as limiting the scope of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the disclosure, and are incorporated herein andconstitute a part of this application. The drawings together with thedescription serve to explain exemplary embodiments of the presentdisclosure. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts. In thedrawings:

FIG. 1 illustrates a schematic view showing the configuration of a powersupply system, according to an embodiment of the disclosure;

FIG. 2 illustrates a schematic view showing the configuration of a powersupply system, according to an embodiment of the disclosure;

FIG. 3 illustrates a plan view showing an arrangement of respectivedevices in the power supply system of FIG. 1, according to an embodimentof the disclosure;

FIG. 4 illustrates a perspective view showing an embodiment of an energystorage device in FIG. 1, according to an embodiment of the disclosure;

FIG. 5 illustrates a perspective view showing attachment of a batterypack to the energy storage device of FIG. 4, according to an embodimentof the disclosure;

FIG. 6 illustrates a perspective view showing another embodiment of theenergy storage device in FIG. 1, according to an embodiment of thedisclosure;

FIG. 7 illustrates a perspective view showing attachment of a batterypack to the energy storage device of FIG. 6, according to an embodimentof the disclosure;

FIG. 8 illustrates a block diagram of the energy storage device in FIG.1, according to an embodiment of the disclosure;

FIG. 9 illustrates a schematic circuit diagram of the energy storagedevice of FIG. 8, according to an embodiment of the disclosure;

FIG. 10 illustrates an internal block diagram of a battery pack in FIG.8, according to an embodiment of the disclosure;

FIG. 11 illustrates an internal block diagram of a server in FIG. 1,according to an embodiment of the disclosure;

FIG. 12 illustrates a flowchart of a method for controlling an energystorage device according to an embodiment of the disclosure;

FIG. 13 illustrates a flowchart of a method for controlling a server,according to an embodiment of the disclosure; and

FIGS. 14, 15A-G, 16A-G, and 17A-B illustrate views referred to fordescription of the control methods of FIGS. 12 or 13, according to anembodiment of the disclosure.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

Reference will now be made in detail to the specific embodiments of thepresent disclosure, examples of which are illustrated in theaccompanying drawings. Wherever possible, the same reference numberswill be used throughout the drawings to refer to the same or like parts.

It should be noted that the suffixes of constituent elements used in thefollowing description, such as “module” and “unit,” are used for ease ofwriting this specification and do not have any particular importance orrole. Accordingly, the terms “module” and “unit” may be usedinterchangeably.

FIG. 1 illustrates a schematic view showing the configuration of a powersupply system. Referring to FIG. 1, power supply system 10 suppliesrenewable power generated by a renewable energy generation device,commercial power from a commercial power plant 900, etc. to an internalpower network 50 through a power distributor 600. Power supply system 10may also supply some of the renewable power generated by the renewableenergy generation device or some of power stored in an energy storagedevice to a power exchange 800 through the power distributor 600.

The renewable energy generation device in power supply system 10 mayinclude a photovoltaic module for generating electricity using sunlight,a wind power module for generating electricity using wind power, and aheat power module for generating electricity using subterranean heat,etc. In an exemplary embodiment, renewable energy generation device caninclude a photovoltaic module 200 which is installable in each building.

Power supply system 10 may supply power into a building, but can beadapted to a variety of applications, settings, and extensions. Forexample, the power supply system 10 may supply power to each home in acollective building or may supply power to each of a plurality ofbuildings in a certain region. In some embodiments, power supply system10 supplies power into a single building. The power supply system 10 ofFIG. 1 may include internal power network 50, a plurality of energystorage devices 100 a, 100 b, . . . , 100 e, the photovoltaic module200, a junction box 300 to perform a power conversion function, a server500, and power distributor 600.

As shown in FIG. 1, a plurality of loads 700 a, 700 b, . . . , 700 e canbe electrically connected to the internal power network 50 throughrespective connection terminals 70 a, 70 b, . . . , 70 e that areconnected to the internal power network 50. Energy storage devices 100a, 100 b, . . . , 100 e are illustrated as being electrically connectedto the internal power network 50 through respective connection terminals60 a, 60 b, . . . , 60 e that are connected to the internal powernetwork 50.

When the energy storage devices 100 a, 100 b, . . . , 100 e operate in acharge mode, each of them may receive alternating current (AC) powerfrom the internal power network 50, convert the received AC power intodirect current (DC) power and store the converted DC power in a batterypack provided therein or attached thereto. Also, when the energy storagedevices 100 a, 100 b, . . . , 100 e operate in a discharge mode, each ofthem may convert DC power stored in the battery pack into AC power andsupply the converted AC power to the internal power network 50.

The operation and internal configuration of each of the energy storagedevices 100 a, 100 b, . . . , 100 e will be described in further detaillater with reference to FIGS. 4 to 10. Briefly, the charge mode anddischarge mode of each of the energy storage devices 100 a, 100 b, . . ., 100 e can be performed based on information about power to store orinformation about power to output to the internal power network 50, sentfrom the server 500.

Server 500 may perform wireless data communication with each of theenergy storage devices 100 a, 100 b, . . . , 100 e. In addition, server500 may perform wireless data communication with the power distributor600. Server 500 may also perform wireless data communication with thejunction box 300, which is electrically connected to the photovoltaicmodule 200 to output AC power. In addition, the server 500 may performwireless data communication with each of the loads 700 a, 700 b, . . . ,700 e. In particular, server 500 may perform wireless data communicationwith powered-on ones of the energy storage devices 100 a, 100 b, . . . ,100 e.

The server 500 may receive a pairing request signal from a powered-onenergy storage device and transmit a pairing response signal including aradio channel allocation signal, etc. to the powered-on energy storagedevice in response to the received pairing request signal. Then, whenpairing with the powered-on energy storage device is completed, theserver 500 may perform wireless data communication with the powered-onenergy storage device over an allocated radio channel.

Generally described, wireless data communication may be performed usingany one of Bluetooth, Radio Frequency Identification (RFID), InfraredData Association (IrDA), Ultra Wideband (UWB), ZigBee, Radio Frequency(RF) and WiFi schemes. Hereinafter, the server 500 will be described asperforming wireless data communication with each of the energy storagedevices 100 a, 100 b, . . . , 100 e, each of the loads 700 a, 700 b, . .. , 700 e, the power distributor 600 or the junction box 300 in the WiFischeme.

In order to effectuate control of the charge mode and the discharge modeoperations of each of the energy storage devices 100 a, 100 b, . . . ,100 e, the server 500 may receive information about renewable powergenerated by the renewable energy generation device, information aboutcommercial power supplied to the internal power network 50, andinformation about load power consumed in the internal power network 50.For example, the server 500 may receive information about renewablepower generated by the photovoltaic module 200 from the junction box 300or power distributor 600 through WiFi communication. In addition, server500 may receive information about commercial power supplied to theinternal power network 50 from the power distributor 600 through WiFicommunication. Server 500 may also receive information about load powerconsumed by each of the loads 700 a, 700 b, . . . , 700 e from acorresponding one of the loads 700 a, 700 b, . . . , 700 e through WiFicommunication. Server 500 may additionally receive information aboutpower stored, storable or additionally storable in a battery pack ofeach of the energy storage devices 100 a, 100 b, . . . , 100 e from acorresponding one of the energy storage devices 100 a, 100 b, . . . ,100 e through WiFi communication.

In an embodiment, server 500 may determine that each of the energystorage devices 100 a, 100 b, . . . , 100 e will operate in the chargemode, based on at least one of the renewable power information, thecommercial power information, the load power information and theadditionally storable power information, and calculate power to store ineach of the energy storage devices 100 a, 100 b, . . . , 100 e in thecharge mode. Server 500 may also determine that each of the energystorage devices 100 a, 100 b, . . . , 100 e will operate in thedischarge mode, based on at least one of the renewable powerinformation, the commercial power information, the load powerinformation and the additionally storable power information, andcalculate power to output from each of the energy storage devices 100 a,100 b, . . . , 100 e to the internal power network 50 in the dischargemode. In addition, server 500 may transmit information about thecalculated power to store or information about the calculated power tooutput to each of the energy storage devices 100 a, 100 b, . . . , 100 ethrough WiFi communication.

In some embodiments, server 500 may be a network server which provides anetwork in the power supply system 10 of FIG. 1, more particularly awireless network server which is capable of performing wireless datacommunication, as stated above, namely, a wireless router. The server500 may also be a network access server (NAS) which is accessibleoutside a network, besides inside the network. Accordingly, outside thenetwork, the user may remotely access the server 500 using a mobileterminal such as a mobile phone to control the operation of the server500. That is, the user may control the operation of the server 500,stated above.

Server 500 may perform data communication with the power exchange 800.For example, server 500 may receive information about the price ofcommercial power supplied from the power exchange 800, peak time powersupply/demand information, etc. from the power exchange 800.Alternatively, the server 500 may receive the information about theprice of the commercial power supplied from the power exchange 800, thepeak time power supply/demand information, etc. through the powerdistributor 600.

Photovoltaic module 200 converts sunlight into DC power and outputs theconverted DC power. Accordingly, the photovoltaic module 200 may includea solar cell module (not shown). The solar cell module may include aplurality of solar cells (not shown). In addition, the solar cell modulemay further include a first sealing member (not shown) disposed on thebottom of the solar cells, a second sealing member (not shown) disposedon the top of the solar cells, a rear substrate (not shown) disposed onthe lower surface of the first sealing member, and a front substrate(not shown) disposed on the upper surface of the second sealing member.Each solar cell can be a semiconductor device which converts solarenergy into electrical energy, and may be a silicon solar cell, acompound semiconductor solar cell, a tandem solar cell, a fuel sensitivesolar cell, a CdTe solar cell or a CIGS solar cell. The solar cells maybe electrically connected in series, in parallel or in series-parallel.

Junction box 300 receives DC power from the solar cell module, convertsthe received DC power into AC power and outputs the converted AC power.The junction box 300 may include a bypass diode (not shown), a DC/DCconverter (not shown), a smoothing capacitor (not shown), and aninverter (not shown). In addition, junction box 300 may further includea wireless communication unit (not shown) for communication with theserver 500. Of note, the junction box 300 may transmit information aboutgenerated solar power to the server 500. The junction box 300 may alsoreceive solar power adjustment information from the server 500 andadjust solar power to output based on the received solar poweradjustment information.

In FIG. 1, solar power output from the junction box 300 is illustratedas being supplied to the internal power network 50 via the powerdistributor 600. In this connection, the power distributor 600 maytransmit the solar power information to the server 500. Although thejunction box 300 is shown in FIG. 1 as being separate from thephotovoltaic module 200, it may be attached on the rear surface of thephotovoltaic module 200, alternatively.

FIG. 2 depicts a schematic view showing the configuration of a powersupply system. The power supply system 10 of FIG. 2 can be configuredsubstantially the same as the power supply system 10 of FIG. 1, with theexception that the solar power output from the junction box 300 isdirectly supplied to the internal power network 50, not via the powerdistributor 600. Accordingly, it may be preferable that the solar powerinformation be transmitted from the junction box 300, not the powerdistributor 600, to the server 500.

FIG. 3 illustrates a plan view showing an arrangement of respectivedevices in the power supply system of FIG. 1. Referring to FIG. 3, theserver 500, among the respective devices in the power supply system 10,may be disposed in a living room. The first energy storage device 100 amay also be disposed in the living room, the second energy storagedevice 100 b in an inner room, the third energy storage device 100 c ina small room, the fourth energy storage device 100 d in a toilet, andthe fifth energy storage device 100 e in a kitchen, respectively. Theseenergy storage devices 100 a, 100 b, . . . , 100 e may be electricallyconnected to the internal power network 50 through the respectiveconnection terminals 60 a, 60 b, . . . , 60 e, as stated previously withreference to FIG. 1.

As shown, a television (TV), which is the first load 700 a, may bedisposed in the living room, a refrigerator, which is the second load700 b, in the kitchen, a washing machine, which is the third load 700 c,in a veranda, an air conditioner, which is the fourth load 700 d, in thesmall room, and a cooker, which is the fifth load 700 e, in the kitchen,respectively. These loads 700 a, 700 b, . . . , 700 e may beelectrically connected to the internal power network 50 through therespective connection terminals 70 a, 70 b, . . . , 70 e, as statedpreviously with reference to FIG. 1. In addition, the power distributor600 may be disposed around the gate of an entrance, the photovoltaicmodule 200 may be disposed at the roof of a building, and the junctionbox 300 may be externally disposed in the vicinity of the powerdistributor 600.

Server 500, which can be disposed in the living room, may performwireless data communication with each of the energy storage devices 100a, 100 b, . . . , 100 e through WiFi communication. The server 500 mayalso perform wireless data communication with each of the loads 700 a,700 b, . . . , 700 e through WiFi communication. In addition, server 500may perform wireless data communication with the power distributor 600or junction box 300 through WiFi communication.

FIG. 4 illustrates a perspective view showing an embodiment of an energystorage device in FIG. 1 and FIG. 5 is a perspective view showingattachment of a battery pack to the energy storage device of FIG. 4.Referring to FIGS. 4 and 5, the energy storage device 100 may include acase 110 having a hexahedral shape and opened at one side thereof, and aconnector 130 coupled with connection terminals of each battery pack.

The case 110 may have a rectangular or cube-like integral structure, andinclude a hole formed at the side 105 of the energy storage device 100.As a result, a plurality of battery packs 400 a, . . . , 400 e may becoupled with the energy storage device 100 at the side 105 thereof. Theconnector 130 may have a hinge structure such that it is coupled withconnection terminals of each of the battery packs 400 a, . . . , 400 e.

In FIG. 5, connector 130 is illustrated as including a positive powerconnection terminal 131 a, a negative power connection terminal 131 b,and a control signal connection terminal 131 c hinged such that they arecoupled with a positive power terminal 431 a, negative power terminal431 b and control signal terminal 431 c of the second battery pack 400b, respectively. It may be preferable that knobs be formed at the frontside of each of the battery packs 400 a, . . . , 400 e in order toreadily attach or detach a corresponding one of the battery packs 400 a,. . . , 400 e to or from the energy storage device 100. Knobs 415 a and415 b can be formed in the second battery pack 400 b.

The second battery pack 400 b is illustrated as being attached on thefirst battery pack 400 a under the condition that the first battery pack400 a is attached to the storage device 100 at the lowermost end of theenergy storage device 100. When the user pushes the second battery pack400 b into the energy storage device 100 thereof with the knobs 415 aand 415 b of the second battery pack 400 b held by him, the positivepower terminal 431 a, negative power terminal 431 b and control signalterminal 431 c of the second battery pack 400 b can be coupled with thepositive power connection terminal 131 a, negative power connectionterminal 131 b and control signal connection terminal 131 c of theenergy storage device 100, respectively.

Although the five battery packs 400 a, . . . , 400 e are illustrated inFIG. 4 as being capable of being coupled with the energy storage device100 at the side 105 thereof, various numbers of be coupled with theenergy storage device 100. In an embodiment, it may be preferable thatthe energy storage device 100 have a width W2 larger than the width W1of the battery pack because it has the internal circuits of FIGS. 8 or 9arranged therein.

In addition, although the second battery pack 400 b is illustrated inFIG. 5 as being attached just above the first battery pack 400 a, itmay, alternatively, be coupled with the energy storage device 100 apartfrom the first battery pack 400 a under the condition that the firstbattery pack 400 a is coupled with the energy storage device 100 at thelowermost end of the energy storage device 100. As a result, because anempty space is defined between the second battery pack 400 b and thefirst battery pack 400 a, a support member (not shown) may be coupledwith the energy storage device 100 thereof to support the empty space.This support member can preferably be of the same size and shape as thebattery pack(s). That is, the support member may have knob-shapedportions, and protrusions corresponding to the respective connectionterminals. This support member may be coupled with the energy storagedevice 100 thereof instead of battery pack(s), not coupled.

FIG. 6 illustrates a perspective view showing another embodiment of theenergy storage device in FIG. 1 and FIG. 7 illustrates a perspectiveview showing attachment of a battery pack to the energy storage deviceof FIG. 6. Referring to FIGS. 6 and 7, the outer appearance of theenergy storage device of FIG. 6 can be substantially the same as that ofthe energy storage device of FIG. 4, with the exception that partitions120 a, 120 b, 120 c and 120 d are arranged in the case 110 of the energystorage device of FIG. 6 to compartmentalize battery packs.

Partitions 120 a, 120 b, 120 c and 120 d may function to guide therespective battery packs 400 a, . . . , 400 e such that the batterypacks 400 a, . . . , 400 e are attached to the energy storage devicethereof. These partitions 120 a, 120 b, 120 c and 120 d may protect therespective battery packs 400 a, . . . , 400 e attached to the energystorage device 100.

FIG. 8 illustrates a block diagram of the energy storage device in FIG.1, and FIG. 9 illustrates a schematic circuit diagram of the energystorage device of FIG. 8. Referring to FIGS. 8 and 9, the energy storagedevice 100 may include a first connector 305, a power converter 310, acontroller 320, a switching unit 330, a network interface 335, anattachment/detachment sensor 340, a second connector 130, and adetachable battery pack 400.

First connector 305 may include only AC power terminals 305 a and 305 b.In some embodiments, energy storage device 100 receives AC power fromthe internal power network 50 and outputs AC power to the internal powernetwork 50. Accordingly, DC power terminals may not be needed, and onlythe AC power terminals 305 a and 305 b can be provided.

In the power supply system of FIG. 1, the AC power terminals 305 a and305 b may receive AC power from the internal power network 50 or outputAC power converted by the energy storage device 100 to the internalpower network 50. Power converter 310 may convert AC power input throughthe first connector 305 into DC power. Then, the converted DC power maybe transferred to the battery pack 400 via the switching unit 330 andthe second connector 130.

Alternatively, power converter 310 may convert DC power stored in thebattery pack 400 into AC power. Then, the converted AC power may betransferred to the above-stated internal power network 50 via the firstconnector 305. Accordingly, the power converter 310 may include abidirectional DC/AC converter.

Switching unit 330 can be disposed between the power converter 310 andthe second connector 130 to perform a switching operation. As a result,the switching unit 330 may supply DC power from the power converter 310to the second connector 130 or supply DC power from the second connector130 to the power converter 310.

Detachable battery pack 400 may include the plurality of battery packs400 a to 400 e as stated previously, and the switching unit 330 mayinclude switches of a number corresponding to the number of the batterypacks 400 a to 400 e. Although the switching unit 330 is illustrated inFIG. 9 as including a first switch 330 a corresponding to the firstbattery pack 400 a, and a second switch 330 b corresponding to thesecond battery pack 400 b, it may further include third to fifthswitches 330 c, 330 d and 330 e corresponding respectively to the thirdto fifth battery packs 400 c, 400 d and 400 e.

Network interface 335 performs data communication with the server 500.For example, when the energy storage device 100 is powered on, thenetwork interface 335 may transmit a pairing request signal to theserver 500. Then, the network interface 335 may receive a pairingresponse signal including information about a radio channel allocated bythe server 500 from the server 500.

After pairing is completed, network interface 335 may receiveinformation about power to store or information about power to output tothe internal power network 50 from the server 500. In addition, afterpairing is completed, the network interface 335 may transmit informationabout power storable in the battery pack 400 to the server 500.

Attachment/detachment sensor 340 senses attachment or detachment of thebattery pack 400. The attachment/detachment sensor 340 may includeattachment/detachment sensing means 340 a, 340 b, . . . of a numbercorresponding to the number of the detachable battery packs 400 a, 400b, . . . Each of the attachment/detachment sensing means 340 a, 340 b, .. . may detect a voltage between a corresponding one of positive powerconnection terminals 130 a, 131 a, . . . and a corresponding one ofnegative power connection terminals 130 b, 131 b, . . . A resistor maybe used for the voltage detection.

When each of the battery packs 400 a, 400 b, . . . is attached, apotential difference between a corresponding one of the positive powerconnection terminals 130 a, 131 a, . . . and a corresponding one of thenegative power connection terminals 130 b, 131 b, . . . corresponds toDC power stored in a corresponding one of the battery packs 400 a, 400b, . . . Each of the attachment/detachment sensing means 340 a, 340 b, .. . senses whether a corresponding one of the battery packs 400 a, 400b, . . . has been attached or detached, by detecting the above potentialdifference.

For example, when the first battery pack 400 a is attached, thepotential difference between the first positive power connectionterminal 130 a and the first negative power connection terminal 130 bmay correspond to DC power stored in the first battery pack 400 a. Thefirst attachment/detachment sensing means 340 a detects the potentialdifference, and may sense that the first battery pack 400 a has beenattached, when the detected potential difference is higher than or equalto a predetermined level.

For another example, when the first battery pack 400 a is detached, thepotential difference between the first positive power connectionterminal 130 a and the first negative power connection terminal 131 amay correspond to 0V. The first attachment/detachment sensing means 340a detects the potential difference, and may sense that the first batterypack 400 a has been detached, when the detected potential difference islower than the predetermined level.

Alternatively, each of the attachment/detachment sensing means 340 a,340 b, . . . may detect current flowing between a corresponding one ofthe positive power connection terminals 130 a, 131 a, . . . and acorresponding one of the negative power connection terminals 130 b, 131b, . . . , . On the other hand, a current sensor, a current transformer(CT) or a shunt resistor may be used for the current detection.

For example, when the first battery pack 400 a is attached, a closedloop may be formed between the first positive power connection terminal130 a and the first negative power connection terminal 130 b, andcurrent may flow through the closed loop. The firstattachment/detachment sensing means 340 a detects the current, and maysense that the first battery pack 400 a has been attached, when thelevel of the detected current is higher than or equal to a predeterminedlevel.

For another example, when the first battery pack 400 a is detached, anopen loop may be formed between the first positive power connectionterminal 130 a and the first negative power connection terminal 130 b,and thus no current may flow. That is, this current may correspond toOA. The first attachment/detachment sensing means 340 a detects thecurrent, and may sense that the first battery pack 400 a has beendetached, when the level of the detected current is lower than thepredetermined level.

The voltage or current detected by each of the attachment/detachmentsensing means 340 a, 340 b, . . . may be transferred to the controller320. Although not shown, the energy storage device 100 may furtherinclude an AC power detector (not shown) for detecting AC power suppliedfrom the first connector 305. For example, the AC power detector (notshown) may detect a voltage or current between the AC power terminals305 a and 305 b of the first connector 305. The detected voltage orcurrent may be transferred to the controller 320.

Controller 320 controls the entire operation of the energy storagedevice 100. In detail, the controller 320 may control the energy storagedevice 100 to convert external input AC power into DC power and storethe converted DC power in the battery pack 400 or convert DC powerstored in the battery pack 400 into AC power and output the converted ACpower externally. That is, the controller 320 may control the energystorage device 100 such that the battery pack 400 operates in the chargemode or discharge mode. This charge mode operation or discharge modeoperation may be performed based on information about power to store orinformation about power to output to the internal power network 50,received from the server 500, as stated previously.

For example, when the information about the power to store is received,the controller 320 may control the energy storage device 100 such thatAC power corresponding to the power to store is input through the firstconnector 305 and then converted into DC power by the power converter310. Then, the controller 320 may control the energy storage device 100to store the converted DC power in the battery pack 400. That is, thecontroller 320 may control the energy storage device 100 such that itoperates in the charge mode. At this time, the controller 320 may turnon a corresponding switch of the switching unit 330. Accordingly, thepower corresponding to the information about the power to store may bestored in the battery pack 400.

For another example, when the information about the power to output tothe internal power network 50 is received, the controller 320 maycontrol the energy storage device 100 such that DC power stored in thebattery pack 400 corresponding to the power to output is supplied to thepower converter 310. Then, the controller 320 may control the energystorage device 100 such that the supplied DC power is converted into ACpower by the power converter 310. That is, the controller 320 maycontrol the energy storage device 100 such that it operates in thedischarge mode. At this time, the controller 320 may turn on acorresponding switch of the switching unit 330. Accordingly, the DCpower stored in the battery pack 400 may be converted and then suppliedto the internal power network 50.

When a plurality of battery packs are attached to the energy storagedevice 100, the controller 320 may receive the levels of DC powersstored respectively in the battery packs and control the energy storagedevice 100 based on the received power levels such that power balancingis performed between the battery packs. For example, in the case wherethe first battery pack 400 a and the second battery pack 400 b areattached to the energy storage device 100, the controller 320 mayreceive respective detected DC power levels of the first battery pack400 a and second battery pack 400 b. Then, the controller 320 maycompare the detected DC power levels with each other and control theenergy storage device 100 based on a result of the comparison to operateany one of the first battery pack 400 a and second battery pack 400 b inthe charge mode and the other one in the discharge mode such that powerbalancing is performed between the first battery pack 400 a and thesecond battery pack 400 b.

For example, when the DC power level of the first battery pack 400 a ishigher than the DC power level of the second battery pack 400 b, thecontroller 320 may control the energy storage device 100 to operate thefirst battery pack 400 a in the discharge mode and the second batterypack 400 b in the charge mode such that the same DC powers are stored inthe respective battery packs 400 a and 400 b. In detail, the controller320 may change connections of the first and second switches in theswitching unit 330.

The controller 320 may receive a signal indicating whether the batterypack 400 has been attached or detached from the attachment/detachmentsensor 340. When the battery pack 400 is attached, the controller 320may immediately control the operation of the switching unit 330 to turnoff a corresponding switch of the switching unit 330. For example, whenthe battery pack 400 is attached to the energy storage device 100,inrush current may be suddenly generated in the energy storage device100, thereby damaging circuit elements in the energy storage device 100.In order to overcome this problem, when the battery pack 400 is attachedto the energy storage device 100, the controller 320 may advantageouslycontrol the operation of the switching unit 330 such that acorresponding switch of the switching unit 330 is kept off for a firstoff period.

The first off period may be longer when the number of battery packsattached is larger. That is, when the number of battery packs attachedis larger, the peak level of inrush current may be higher. To overcomethis surge of inrush current, it may be preferable that the off periodof a corresponding switch of the switching unit 330 be controlled to belonger. Next, after the first off period, the battery pack 400 mayoperate in the charge mode or discharge mode under the control of thecontroller 320. That is, a corresponding switch of the switching unit330 may be turned on.

In an embodiment, when the battery pack 400 is detached from the energystorage device 100, inrush current may be suddenly generated in theenergy storage device 100, thereby damaging circuit elements in theenergy storage device 100. In order to prevent a spike of inrushcurrent, the controller 320 may control the operation of the switchingunit 330 such that a corresponding switch of the switching unit 330 iskept off for a second off period when the battery pack 400 is detachedfrom the energy storage device 100.

The second off period may be longer when the number of battery packsattached is larger. That is, when the number of battery packs attachedis larger, the peak level of inrush current may be higher. To preventthis, it can be preferable that the off period of a corresponding switchof the switching unit 330 be controlled to be longer. Accordingly, thecontroller 320 may control the operation of a switch of thebidirectional DC/AC converter in the power converter 310.

In addition, when the second battery pack 400 b is attached under thecondition that the first battery pack 400 a operates in the charge mode,the controller 320 may turn off both the switches 330 a and 330 b of theswitching unit 330 for the first off period and then control the energystorage device 100 such that the second battery pack 400 b, not thefirst battery pack 400 a, operates in the charge mode. After the firstoff period, the first switch 330 a may be kept off and the second switch330 b may be turned on. Accordingly, the battery packs may be controlledto be evenly charged.

FIG. 10 depicts an internal block diagram of the battery pack in FIG. 8.Referring to FIG. 10, the battery pack 400 includes a battery pack case410, and a connector 430, a battery controller 460, a battery cell unit480, and a temperature adjuster 470 provided in the battery pack case410.

Connector 430 may have protruded connection terminals to be attached tothe second connector 130 of the energy storage device 100. In detail,the connector 430 may have connection terminals such as the positivepower terminal 431 a, negative power terminal 431 b and control signalterminal 431 c. These terminals 431 a, 431 b and 431 c are coupled withthe hinged connection terminals 131 a, 131 b and 131 c of the energystorage device 100, respectively, when the battery pack 400 is attached.

The battery cell unit 480 includes a plurality of battery cells. Thesebattery cells may be connected in series, in parallel or inseries-parallel combination. Although not shown, the battery cell unit480 may be electrically connected to the positive power terminal 431 aand the negative power terminal 431 b.

The temperature adjuster 470 adjusts the temperature of the battery cellunit 480. Temperature adjuster 470 may include temperature sensing means(not shown) to sense the temperature of the battery cell unit 480. Inaddition, the temperature adjuster 470 may further include fan drivingmeans (not shown) to drive a fan based on the sensed temperature so asto lower the temperature of the battery cell unit 480. In order toimprove efficiency of the temperature adjustment, the fan driving meanscan be preferably disposed in an area corresponding to an area in whichall the battery cells are arranged.

Battery controller 460 performs the overall control of the battery pack400. For example, when the temperature of the battery cell unit 480rises over a predetermined temperature, the battery controller 460 maycontrol the temperature adjuster 470 to lower the temperature of thebattery cell unit 480. In addition, the battery controller 460 maybalance DC powers stored respectively in the battery cells in thebattery cell unit 480. That is, the battery controller 460 may detectthe DC powers stored respectively in the battery cells and balance theDC power stored in each of the battery cells based on a result of thedetection.

When the battery pack 400 is attached to the connector 130 of the energystorage device 100, the battery controller 460 may transfer statusinformation (a temperature, the level of power stored, etc.) of thebattery pack 400 to the energy storage device 100 through the controlsignal terminal 431 c. This status information may be input to thecontroller 320 of the energy storage device 100. The battery controller460 may receive status information (the level of power needed, etc.) ofthe energy storage device 100 through the control signal terminal 431 c.

FIG. 11 illustrates an internal block diagram of the server in FIG. 1.Referring to FIG. 11, server 500 may be a network server, and include anetwork interface 530, a storage unit 540, and a processor 520. Theserver 500 may wirelessly exchange data with respective devices in thepower supply system, and, particularly, control the plurality of energystorage devices 100 a, 100 b, . . . , 100 e such that they operate inthe charge mode or discharge mode.

Network interface 530 may receive a pairing request signal from apowered-on one of the energy storage devices 100 a, 100 b, . . . , 100 eand transmit a pairing response signal generated by the processor 520 tothe powered-on energy storage device in response to the received pairingrequest signal. The pairing response signal may include a radio channelallocation signal. For control of the charge mode and discharge modeoperations of each of the energy storage devices 100 a, 100 b, . . . ,100 e, the network interface 530 may receive information about renewablepower generated by the renewable energy generation device, informationabout commercial power supplied to the internal power network 50, andinformation about load power consumed in the internal power network 50.

For example, the network interface 530 may receive information aboutrenewable power generated by the photovoltaic module 200 from thejunction box 300 or power distributor 600 through WiFi communication. Inaddition, the network interface 530 may receive information aboutcommercial power supplied to the internal power network 50 from thepower distributor 600 through WiFi communication. Network interface 530may also receive information about load power consumed by each of theloads 700 a, 700 b, . . . , 700 e from a corresponding one of the loads700 a, 700 b, . . . , 700 e through WiFi communication. The networkinterface 530 may receive information about power stored, storable oradditionally storable in the battery pack of each of the energy storagedevices 100 a, 100 b, . . . , 100 e from a corresponding one of theenergy storage devices 100 a, 100 b, . . . , 100 e through WiFicommunication.

Processor 520 controls the entire operation of the server 500. Forexample, the processor 520 may determine that each of the energy storagedevices 100 a, 100 b, . . . , 100 e will operate in the charge mode,based on at least one of the renewable power information, the commercialpower information, the load power information and the additionallystorable power information, received by the network interface 530, andcalculate power to store in each of the energy storage devices 100 a,100 b, . . . , 100 e in the charge mode.

The processor 520 may also determine that each of the energy storagedevices 100 a, 100 b, . . . , 100 e will operate in the discharge mode,based on at least one of the renewable power information, the commercialpower information, the load power information and the additionallystorable power information, and calculate power to output from each ofthe energy storage devices 100 a, 100 b, . . . , 100 e to the internalpower network 50 in the discharge mode.

Storage unit 540 may store external Internet protocol (IP) addresses andinternally allocated virtual IP addresses for provision of a wirelessnetwork, and radio channel names, frequency ranges, securityinformation, etc. corresponding respectively to the virtual IPaddresses. Also, the storage unit 540 may store device names, etc. ofrespective devices networked through the server 500.

FIG. 12 illustrates a flowchart of a method for controlling an energystorage device, FIG. 13 is a flowchart illustrating a method forcontrolling a server, and FIGS. 14, 15A-G, 16A-G, and 17A-B illustrateviews referred to for description of the control methods of FIGS. 12 or13.

Referring to FIGS. 12-14, 15A-G, 16A-G, and 17A-B, the controller 320 ofthe energy storage device 100 determines whether the energy storagedevice 100 has been powered on (S1210). If the energy storage device 100has been powered on, it transmits a pairing request signal to the server500 (S1220). Then, the energy storage device 100 receives a pairingresponse signal from the server 500 (S1230).

As shown in FIG. 15A, when a power plug 112 of the energy storage device100 is connected to a power receptacle 60, the energy storage device 100is electrically connected to the internal power network 50. In theenergy storage device 100, AC power supplied from the internal powernetwork 50 can be inputted through the first connector 305 and thenconverted into DC power by the power converter 310. The converted DCpower may be supplied as operating power to each module of the energystorage device 100. As a result, when the operating power is input, thecontroller 320 may determine that the energy storage device 100 has beenpowered on, and then control the energy storage device 100 to transmit apairing request signal indicating that the energy storage device 100 hasbeen activated to the server 500 through the network interface 335.

Then, the server 500 determines whether the pairing request signal hasbeen received (S1320), and transmits a pairing response signal to thecorresponding energy storage device 100 upon determining that thepairing request signal has been received (S1330).

In the server 500, the network interface 530 transfers the pairingrequest signal received from the energy storage device 100 to theprocessor 520. Then, the processor 520 can generate a pairing responsesignal including information about a radio channel allocated to thecorresponding energy storage device 100 in response to the pairingrequest signal, and then control the server 500 to transmit thegenerated pairing response signal to the energy storage device 100through the network interface 530.

FIG. 15B illustrates that a pairing request signal Sp1 is transmittedfrom the energy storage device 100 to the server 500 and a pairingresponse signal Sp2 is transmitted from the server 500 to the energystorage device 100. Of note, step S1410 of FIG. 14 corresponds to stepS1210 of FIG. 12, step S1420 of FIG. 14 corresponds to step S1220 ofFIG. 12 and step S1320 of FIG. 13, and step S1430 of FIG. 14 correspondsto step S1230 of FIG. 12 and step S1330 of FIG. 13.

As illustrated in FIG. 13, subsequent to step S1330, server 500 mayreceive information about commercial power supplied to the internalpower network 50 and renewable power information (S1332). Server 500 maythen receive information about load power consumed in the internal powernetwork 50 (S1334). The server 500 may then calculate power to store inthe energy storage device 100 or power to output from the energy storagedevice 100 (S1338). Moving to block S1340, the server 500 may thentransmit information about the calculated power to store or informationabout the calculated power to output to the energy storage device 100.

In some embodiments, server 500 may receive information about solarpower generated by the photovoltaic module 200 or information aboutsolar power converted by the junction box 300 through the networkinterface 530. This solar power information may be transmitted from thejunction box 500 or power distributor 600 through WiFi communication.The network interface 530 of the server 500 may further receivecommercial power information, load power information, and additionallystorable power information. The commercial power information may betransmitted from the power distributor 600 through WiFi communication.

The load power information described herein may be transmitted from thepower distributor 600. For example, provided that the power distributor600 has a wattmeter which calculates the amount of power consumed in theinternal power network 50, it will calculate load power through thewattmeter. Information about the load power calculated by the powerdistributor 600 may be transmitted to the server 500 through WiFicommunication. Alternatively, load power may be calculated by a powercalculator provided in each of the loads 700 a, 700 b, . . . , 700 e,and information about the calculated load power may then be transmittedto the server 500 through WiFi communication. The server 500 may alsoreceive information about power additionally storable in the batterypack 400 from the energy storage device 100 through WiFi communication.

FIG. 15C illustrates additional power information that may betransmitted, stored, and utilized by the systems, devices, and methodsdisclosed herein. As shown, information IPes is transmitted from theenergy storage device 100 to the server 500. In addition, the followinginformation may be transmitted from the power distributor 600 to theserver 500: information IPso about renewable power generated by thephotovoltaic module 200, information IPco about commercial powersupplied to the internal power network 50, and information IP_(L) aboutload power consumed by each load.

With continued to reference to FIGS. 15C and 14, the processor 520 ofthe server 500 can determine whether each of the energy storage devices100 a, 100 b, . . . , 100 e will operate in the charge mode or dischargemode, based on at least one of the received renewable power informationIPso, commercial power information IPco, load power information IP_(L)and additionally storable power information IPes. If it is determinedthat each of the energy storage devices 100 a, 100 b, . . . , 100 e willoperate in the charge mode, the processor 520 of the server 500 maycalculate power to store in each of the energy storage devices 100 a,100 b, . . . , 100 e. In addition, if it is determined that each of theenergy storage devices 100 a, 100 b, . . . , 100 e will operate in thedischarge mode, the processor 520 may calculate power to output fromeach of the energy storage devices 100 a, 100 b, . . . , 100 e to theinternal power network 50.

The network interface 530 of the server 500 may transmit informationabout the calculated power to store to each of the energy storagedevices 100 a, 100 b, . . . , 100 e in the charge mode. Networkinterface 530 of the server 500 may also transmit information about thecalculated power to output to each of the energy storage devices 100 a,100 b, . . . , 100 e in the discharge mode. The information about thepower to store may include at least one of a charge start command and acharge stop command. In addition, the information about the power tooutput may include at least one of a discharge start command and adischarge stop command.

Of note, step S1432 of FIG. 14 corresponds to step S1332 of FIG. 13,step S1438 of FIG. 14 corresponds to step S1338 of FIG. 13, and stepS1440 of FIG. 14 corresponds to step S1240 of FIG. 12 and step S1340 ofFIG. 13.

Referring now to FIG. 12, the controller 320 of the energy storagedevice 100 determines whether information about power to store has beenreceived from the server 500 (S1240). If the information about the powerto store has been received from the server 500, the energy storagedevice 100 can receive AC power from the internal power network 50 basedon the received information about the power to store, convert thereceived AC power into DC power, and store the converted DC power in thebattery pack 400 (S1250).

FIG. 15D illustrates the transmission of information IPps about power tostore from the server 500 to the energy storage device 100. Uponreceiving the information IPps about the power to store from the server500, the network interface 335 of the energy storage device 100 cantransfer the received information to the controller 320. Upon receivingthe information IPps about the power to store from the network interface335, the controller 320 may control the energy storage device 100 suchthat AC power corresponding to the power to store is input through thefirst connector 305 and then converted into DC power by the powerconverter 310. Then, the controller 320 may control the energy storagedevice 100 to store the converted DC power in the battery pack 400.Accordingly, the power corresponding to the information about the powerto store may be stored in the battery pack 400.

FIG. 15E illustrates that power Pps, namely AC power, corresponding tothe information IPps about the power to store can be supplied from theinternal power network 50 to the energy storage device 100. Of note,step S1450 of FIG. 14 corresponds to step S1250 of FIG. 12. As shown inFIG. 12, the controller 320 of the energy storage device 100 candetermine whether information about power to output has been receivedfrom the server 500 (S1260). If the information about the power tooutput has been received from the server 500, the energy storage device100 converts DC power stored therein into AC power based on the receivedinformation about the power to output and outputs the converted AC powerto the internal power network 50 (S1270).

FIG. 15F illustrates that information IPpo about power to output can betransmitted from the server 500 to the energy storage device 100. Uponreceiving the information IPpo about the power to output from the server500, the network interface 335 of the energy storage device 100transfers the received information to the controller 320. Upon receivingthe information IPpo about the power to output from the networkinterface 335, the controller 320 may control the energy storage device100 such that DC power stored in the battery pack 400 corresponding tothe power to output is supplied to the power converter 310. Then, thecontroller 320 may control the energy storage device 100 such that thesupplied DC power is converted into AC power by the power converter 310.Therefore, the DC power stored in the battery pack 400 may be convertedand then supplied to the internal power network 50.

FIG. 15G illustrates that power Ppo, namely AC power, corresponding tothe information IPpo about the power to output is supplied from theenergy storage device 100 to the internal power network 50. Accordingly,power stored in the energy storage device 100 may be supplied to theinternal power network 50, thereby reducing consumption of commercial ACpower. That is, renewable energy, such as solar power from thephotovoltaic module 200, is stored in the energy storage device 100 andthen supplied to the internal power network 50, so that the energy maybe efficiently consumed. In addition, because the consumption of thecommercial AC power is reduced, the cost thereof is reduced.

In exemplary embodiments, whenever an energy storage device is added orremoved, the server 500 may recognize the energy storage device additionor removal, receive information about the added or removed energystorage device and update the existing information with the receivedinformation. When the added energy storage device is powered on, theserver 500 may perform pairing, etc. with the added energy storagedevice to newly store information about the added energy storage device,and allocate a radio channel for wireless data communication to theadded energy storage device. Conversely, when an existing energy storagedevice is powered off, a radio channel in use is no longer being used.As a result, the server 500 may recognize that the existing energystorage device corresponding to the radio channel has been powered off,and update information about the powered-off energy storage device tofree up the communication channel.

Server 500 may perform a control operation based on information aboutrenewable power generated by the renewable energy generation device,information about commercial power supplied to the internal powernetwork 50, information about load power consumed in the internal powernetwork 50, etc. such that the commercial power is used at the minimumand the renewable power is used at the maximum. That is, the server 500may provide corresponding information to the power distributor 600 suchthat all of the renewable power is supplied to the internal powernetwork 50, and provide corresponding information to the powerdistributor 600 such that only a minimum amount of the commercial poweris supplied to the internal power network 50 in consideration of theinternal load power information.

The server 500 may provide a smart grid service. That is, in the casewhere the price of the commercial power is different according to timezones, the server 500 may perform a control operation such that thecommercial power is supplied to the internal power network 50 at a timezone at which the commercial power is cheap. Also, the server 500 mayperform a control operation such that the commercial power supplied tothe internal power network 50 is stored in each energy storage device.For example, the server 500 may perform a control operation such thatpower stored in an energy storage device is supplied to the internalpower network 50 at a time zone at which the commercial power isexpensive. In some embodiments, commercial power price information maybe transmitted to the server 500 through the power exchange 800 or powerdistributor 600.

FIGS. 16A to 16E correspond to FIGS. 15C to 15G, respectively. In theillustrated embodiments, server 500 receives or transmits informationfrom or to a plurality of energy storage devices. That is, FIG. 16Aillustrates that additionally storable power information IPes1, IPes2, .. . , IPes5 may be transmitted from the respective energy storagedevices 100 a, 100 b, . . . , 100 e to the server 500. In theillustrated embodiments, FIG. 16A shows the transmission from the powerdistributor 600 to the server 500 of the following parameters:information IPso about renewable power generated by the photovoltaicmodule 200, information IPco about commercial power supplied to theinternal power network 50 and information IP_(L) about load powerconsumed by each load.

FIG. 16B illustrates that information IPps1, IPps2, . . . , IPps5 aboutpowers to be stored can be transmitted from the server 500 to therespective energy storage devices 100 a, 100 b, . . . , 100 e.

FIG. 16C illustrates that powers Pps1, Pps2, . . . , Pps5, namely ACpowers, corresponding respectively to the information IPps1, IPps2, . .. , IPps5 about the powers to be stored can be supplied from theinternal power network 50 to the respective energy storage devices 100a, 100 b, . . . , 100 e.

FIG. 16D illustrates that information IPpo1, IPpo2, . . . , IPpo5 aboutpowers to be output can be transmitted from the server 500 to therespective energy storage devices 100 a, 100 b, . . . , 100 e.

FIG. 16E illustrates that powers Ppo1, Ppo2, . . . , Ppo5, namely ACpowers, corresponding respectively to the information IPpo1, IPpo2, . .. , IPpo5 about the powers to be output may be supplied from therespective energy storage devices 100 a, 100 b, . . . , 100 e to theinternal power network 50.

In an embodiment, all of the energy storage devices 100 a, 100 b, . . ., 100 e may operate in the charge mode as shown in FIG. 16C or in thedischarge mode as shown in FIG. 16E. Alternatively, some of the energystorage devices 100 a, 100 b, . . . , 100 e may operate in the dischargemode and the others may operate in the charge mode.

FIG. 16F illustrates the transmission from the server 500 to therespective energy storage devices 100 a, 100 b, . . . , 100 e ofinformation IPps1 about the power to store and the information IPpo1,IPpo2, . . . , IPpo5 about the powers to be output.

FIG. 16G illustrates supplying from the internal power network 50 to thefirst energy storage device 100 a of the power Pps1, namely AC power,corresponding to the information IPps1 about the power to store. FIG.16G illustrates that the powers Ppo2, . . . , Ppo5, namely AC powers,corresponding respectively to the information IPpo2, . . . , IPpo5 aboutthe powers to be output can be supplied from the second to fifth energystorage devices 100 a, 100 b, . . . , 100 e to the internal powernetwork 50.

The power supply system 10 may supply some of the renewable powergenerated by the renewable energy generation device or some of thepowers stored in the energy storage devices to the power exchange 800through the power distributor 600. Accordingly, the processor 520 of theserver 500 may calculate power to output to the outside of the internalpower network 50 based on at least one of the load power informationIP_(L), the commercial power information IPco, the renewable powerinformation Ipso and the information about the power stored in eachenergy storage device. That is, the processor 520 may calculate externaloutput power to be transmitted to the power exchange 800.

Network interface 530 of server 500 may transmit information about thecalculated external output power to power distributor 600, whichdistributes the commercial power to the internal power network 50. As aresult, power distributor 600 can perform a control operation such thatsome of AC power supplied to the internal power network 50 is outputtedexternally, such as to the power exchange 800. Server 500 may perform acontrol operation such that some of the renewable power generated by therenewable energy generation device or some of the powers stored in theenergy storage devices is supplied to the power exchange 800 through thepower distributor 600 when there is a power transmission request fromthe power exchange 800 at a peak power consumption time zone.

FIG. 17A illustrates that external output power information IPdi can betransmitted to the power distributor 600.

FIG. 17B illustrates that external output power Pdi, namely AC power,corresponding to the external output power information IPdi can betransmitted from the power distributor 600 to the power exchange 800.Accordingly, the disclosed devices, systems, servers, and methodseffectuate more efficient use of power.

The plurality of energy storage devices 100 a, 100 b, . . . , 100 e andthe plurality of loads 700 a, 700 b, . . . , 700 e in the power supplysystem 10 can have a one-to-one correspondence. Alternatively, aplurality of loads may be assigned to one energy storage device tocorrespond thereto. In particular, one energy storage device maycorrespond to loads adjacent thereto.

For example, one energy storage device may supply power stored thereinto the internal power network 50 according to power consumption of aplurality of loads, and the corresponding loads may immediately consumeAC power supplied from the energy storage device. That is, in the powersupply system 10, an energy storage device corresponding to a localposition where power consumption is required may operate in thedischarge mode, thereby making it possible to efficiently manage power.The server 500 may store information about the position of each energystorage device, information about the position of each load, andinformation about power consumption of each load.

The information about the position of each energy storage device may becalculated based on the strength of a signal, etc. when pairing with thecorresponding energy storage device is performed. Also, the informationabout the position of each load may be calculated based on the strengthof a signal, etc. when pairing between the corresponding load and theserver is performed.

The energy storage devices, servers, and methods for controlling thesame are not limited to the configurations and methods of theabove-described embodiments, and all or some of these embodiments may beselectively combined and configured so that those embodiments may besubjected to various modifications.

In addition, the energy storage device control method or server controlmethod of the present invention may be implemented in a recording mediumreadable by the processor of the energy storage device or server byprocessor-readable codes. The processor-readable recording medium mayinclude all types of recording units in which processor-readable datamay be stored. For example, the processor-readable recording medium mayinclude a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, anoptical data storage, or the like. The processor-readable recordingmedium may also be implemented in the form of a carrier wave such astransmission over the Internet. Also, the processor-readable recordingmedium may be distributed to networked computer systems andprocessor-readable codes may be stored and executed in the computersystems in a distributed manner.

As is apparent from the above description, energy storage device mayconvert AC power from an internal power network into DC power and storethe converted DC power, or convert DC power stored therein into AC powerand output the converted AC power to the internal power network. Thiscan be based on information about power to store or information aboutpower to output, received from a server. Therefore, energy is moreefficiently and easily stored in the energy storage device and controlsystem.

For example, a power converter of the energy storage device may receiveAC power and convert the received AC power into DC power, or convert DCpower stored in a battery pack into AC power and output the converted ACpower. As a result, the power converter may not require a separate DC/DCconverter, allowing it to be more easily configured. In addition, whenthe energy storage device is powered on, it may perform pairing with theserver to operate under control of the server, thereby increasing userconvenience.

In an embodiment, when an energy storage device is powered on, theserver may perform pairing with the powered-on energy storage device,thereby simplifying control of energy storage devices provided in thesame internal power network. Server may allocate different radiochannels to a plurality of energy storage devices, so as to efficientlycontrol the respective energy storage devices.

The server may calculate power to store in at least one energy storagedevice through the internal power network or power to output from theenergy storage device to the internal power network based on at leastone of information about renewable power generated by a renewable energygeneration device, information about commercial power supplied to theinternal power network and information about load power consumed in theinternal power network, and transmit information about the calculatedpower to store or information about the calculated power to be output tothe energy storage device. Therefore, the server may efficiently controlenergy storage devices connected to the internal power network.

In addition, server may calculate power to be output to the outside ofthe internal power network based on at least one of the informationabout the renewable power generated by the renewable energy generationdevice, the information about the commercial power supplied to theinternal power network and the information about the load power consumedin the internal power network, and transmit information about thecalculated output power to a power distributor connected to the internalpower network, so as to control the power distributor such that thecorresponding power is externally output.

It will be apparent to those skilled in the art that variousmodifications and variation can be made in the present invention withoutdeparting from the spirit or scope of the invention. Thus, it isintended that the present invention cover the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

What is claimed is:
 1. An energy storage device comprising: at least onebattery pack; a network interface to exchange data with a server; aconnector to receive alternating current (AC) power from an internalpower network or outputting AC power to the internal power network; anda power converter to convert the AC power from the internal powernetwork into direct current (DC) power based on the information aboutthe power to store when information about power to store is receivedfrom the server, or, convert DC power stored in the battery pack into ACpower based on the information about the power to output wheninformation about power to be output to the internal power network isreceived from the server.
 2. The energy storage device according toclaim 1, further comprising: a controller to control the power converterto operate the energy storage device in a charge mode when theinformation about the power to store is received from the server, and,control the power converter to operate the energy storage device in adischarge mode when the information about the power to output to theinternal power network is received from the server.
 3. The energystorage device according to claim 2, further comprising: a switchingunit to perform a switching operation that charges the DC powerconverted by the power converter in the battery pack in the charge mode.4. The energy storage device according to claim 1, further comprising: asecond connector to or from which the at least one battery pack isattached or detached; and a controller to perform a control operation toturn off an electrical connection between a first battery pack and asecond battery pack for a predetermined period when the second batterypack is additionally attached to the second connector under a conditionthat the first battery pack is attached to the second connector.
 5. Theenergy storage device according to claim 1, wherein the networkinterface transmits a pairing request signal to the server when theenergy storage device is powered on, and then receives a pairingresponse signal from the server.
 6. The energy storage device accordingto claim 1, wherein the network interface receives the information aboutthe power to store and the information about the power to output to theinternal power network over a radio channel different from that ofanother energy storage device.
 7. A server comprising: a networkinterface configured to receive information about renewable powergenerated by a renewable energy generation device, information aboutcommercial power supplied to an internal power network and informationabout load power consumed in the internal power network; and a processorto calculate power to store in at least one energy storage devicethrough the internal power network or power to output from the energystorage device to the internal power network based on at least one ofthe load power information, the commercial power information and therenewable power information, wherein the network interface transmitsinformation about the calculated power to store or information about thecalculated power to output to the energy storage device.
 8. The serveraccording to claim 7, wherein the network interface receives a pairingrequest signal from the energy storage device and transmits a pairingresponse signal to the energy storage device.
 9. The server according toclaim 7, wherein the network interface receives information about powerstored, storable or additionally storable in the energy storage devicefrom the energy storage device.
 10. The server according to claim 7,wherein: the processor performs a control operation to allocatedifferent radio channels to a plurality of energy storage devices; andthe network interface transmits the information about the calculatedpower to store or the information about the calculated power to outputto each of the energy storage devices over a corresponding one of thedifferent radio channels.
 11. The server according to claim 7, whereinthe network interface receives the information about the renewable powergenerated by the renewable energy generation device, the informationabout the commercial power supplied to the internal power network andthe information about the load power consumed in the internal powernetwork from a power distributor, the power distributor distributing thecommercial power to the internal power network.
 12. The server accordingto claim 7, wherein: the processor calculates power to output to theoutside of the internal power network based on at least one of the loadpower information, the commercial power information, the renewable powerinformation and information about power stored in the energy storagedevice; and the network interface transmits information about thecalculated power to output to the outside of the internal power networkto a power distributor, the power distributor distributing thecommercial power to the internal power network.
 13. The server accordingto claim 12, wherein: the network interface exchanges data with thepower distributor over a different radio channel with another energystorage device.
 14. A method for controlling an energy storage device,the method comprising: converting alternating current (AC) power from aninternal power network into direct current (DC) power based oninformation about power to store when the information about the power tostore is received from a server; storing the converted DC power;converting the stored DC power into AC power based on information aboutpower to output to the internal power network when the information aboutthe power to output is received from the server; and outputting theconverted AC power to the internal power network.
 15. The methodaccording to claim 14, further comprising: transmitting a pairingrequest signal to the server when the energy storage device is poweredon; and receiving a pairing response signal from the server.
 16. Themethod according to claim 14, wherein the information about the power tostore and the information about the power to output to the internalpower network are received over a radio channel different from that ofanother energy storage device.
 17. A method for controlling a server,the method comprising: receiving information about renewable powergenerated by a renewable energy generation device and information aboutcommercial power supplied to an internal power network; receivinginformation about load power consumed in the internal power network;calculating power to store in an energy storage device through theinternal power network or power to output from the energy storage deviceto the internal power network based on at least one of the load powerinformation, the commercial power information and the renewable powerinformation; and transmitting information about the calculated power tostore or information about the calculated power to output to the energystorage device.
 18. The method according to claim 17, furthercomprising: receiving a pairing request signal from the energy storagedevice; and transmitting a pairing response signal to the energy storagedevice.
 19. The method according to claim 17, further comprising:receiving information about power stored, storable or additionallystorable in the energy storage device from the energy storage device.20. The method according to claim 17, further comprising: allocatingdifferent radio channels to a plurality of energy storage devices,wherein the transmitting comprises transmitting the information aboutthe calculated power to store or the information about the calculatedpower to output to each of the energy storage devices over acorresponding one of the different radio channels.